The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
A large-sized bus (e.g. an urban bus, an express bus, or a tourist bus) is provided with a large-capacity battery relay in order to drive loads mounted inside or outside the bus without using a start key.
For example, when a battery switch is pushed, irrespective of operation of the start key, contact voltage generated as a result of contact between contacts of the battery relay is applied to loads, such as a starter motor and a roof air conditioner.
When the battery switch is turned off during the operation of the loads, the contacts of the battery relay are separated from each other with the result that no voltage is applied to the loads. When the contacts of the battery relay come into contact with each other and/or are separated from each other, the contacts of the battery relay are frequently damaged (e.g. due to arcing).
Furthermore, in a case in which a large-capacity load is further connected to the battery relay, the quality of the battery relay is reduced due to the increase of the large-capacity load.